Index: wp-includes/functions.php
===================================================================
--- wp-includes/functions.php	(revision 21282)
+++ wp-includes/functions.php	(working copy)
@@ -5,7 +5,8 @@
  * @package WordPress
  */
 
-require( ABSPATH . WPINC . '/option.php' );
+if ( version_compare( $required_php_version, phpversion(), '<=' ) )
+	require( ABSPATH . WPINC . '/option.php' );
 
 /**
  * Converts given date string into a different format.